It's a Living (1980)

S3E15 Jewel Heist

When a royal princess arrives for a visit, a group of terrorists sets their sights on her lavish diamond necklace. Meanwhile, Dot inadvertently comes across a napkin laced with drugs meant for the princess. As the plot unfolds, Dot must navigate the chaos to protect the princess and thwart the villains’ scheme, all while unraveling the mystery surrounding the dangerous napkin.