If you’re not a heavy Bebo user, you might not be aware of The Secret World of Sam King. It’s the social network’s latest online TV drama, following in the soapsteps of KateModern. Except this one’s got a strong music tie-in – it’s shot in the Universal Music building, and features regular cameos from UMG artists.The label tells us that 5.4 million people have now tuned into the show, which is averaging 100,000 viewers a day on Bebo, plus more on YouTube. And now the show is getting a bit more interactive.How? As part of a storyline about shooting a video for A&M artist Nick Harrison, the show’s lead character Sam has invited viewers to become extras, via a blog post on Bebo. It’s due to be shot next Monday, and will feature in the show the next day. This is the first time online fans have been invited to actually take part in the show, apparently.