Lisa: Charlie Norfolk

Dan: Chris Young

Adam Mosby is on his first night as Duty Officer at the Government listening station called the Hive, when his computer starts to go crazy. All over the building, electrical equipment is malfunctioning. Security move quickly and are shocked to find that their intruder is a 14 year old girl! - CARLY.

Ros and Alex go to the Hive to help the staff there with the problems created by Carly in the computing systems. Ed and Beckett remain at the Bureau where they are working on plans to protect a highly valuable, and very ancient, Funeral Mask, which is arriving from South America for an Exhibition.

At the Hive, Ros finds it difficult to get through to Carly, but admires her technical brilliance. Because Carly has no parents and is plainly in need of being channeled away from crime, Jan plans for Carly to attend a special technical academy where her skills scan be nurtured. Jan puts Ros in charge of ensuring that Carly gains a place at The Academy.

Alex meets Adam, and it is clear she takes a shine to him. They discover that Carly has introduced a "random mailer' into the Hive's computers, scattering vital files across cyberspace. Some information has ended up on the computer of a bird watching magazine.

Adam and Alex visit the magazine office, and Alex is horrified to discover that the Bureau security plans for the Mask exhibition are on the magazine's computer. The only way they could have got to the magazine is from the Hive - but Mask security is a Bureau responsibility. How did these plans get on to a Hive computer?

At the airport, Beckett and Ed are being observed as they wait for the Mask to arrive. There is an attempt to steal the Mask, but they are able to outwit the thieves. Back at the Bureau they identify one of their attackers as LISA.

Carly causes trouble at the Bureau when she demonstrates her "power-sucker' device which drains electricity. Filsinger, a Hive official, witnesses this as he calls into the Bureau bringing background information on Lisa. Alex is distressed to see that Filsinger's information suggests Lisa is an associate of Adam Mosby's!

Filsinger suggests he take Carly off Ros's hands for a while .... Once out of the office, Filsinger introduces Carly to none other than Lisa, who tried to steal the mask at the airport, and her accomplice, Dan. It is Filsinger, not Adam, who is behind the attempt to steal the Mask. Filsinger and Lisa trick Carly into helping them get round the security at the museum. They tell her that stealing the mask will be a way of highlighting any weaknesses in Ros's security procedures.

Ed and Ros are at the museum when they see the effects of Carry’s power-sucker in action. They investigate - but are imprisoned in the basement by Filsinger, while Carly steals the mask under Filsinger's direction.

Carly soon realises that she has been duped, and Filsinger and Lisa only want the valuable Mask for themselves. Carly runs away with the mask, pursued by Filsinger, Lisa and Dan. Once Ros escapes from the museum, she tracks Carly to a shopping arcade, but Filsinger and the others catch them both. Carly has hidden the mask but refuses to say where.

Ros and Carly are taken to Lisa's workshop, where they are imprisoned at the bottom of a lift shaft. Even though they do not have the Mask, Lisa and Filsinger demand a ransom for it. Jan and Beckett are not sure that it is a bluff and have to go along with a ransom hand-over as a means to capture them.

Carly escapes from the lift and uses Ros’s radio to tell Alex that she hid the mask in an electrical store. Alex and Adam, working together, recover the mask.

Jan meets Filsinger with the ransom money, whilst Beckett watches from concealment. When Jan and Beckett hear from Alex that the Mask has been recovered, they are able to trap Filsinger and Lisa before they can escape with any money.

Ed arrives at the workshop, and a fight ensues with Dan - during which a laser machine is accidentally turned on. The laser starts to cut through the lift cable, with Ros still trapped beneath the lift cage. Carly uses her power-sucker to turn off the power and Ed pulls Ros out of the shaft just in time.