As Britain finally throws off the shackles of endless lockdowns and restrictions, the economy stands poised to unfurl at welcome speed. But there is one group of companies that is making a particularly powerful resurgence. Share prices have been steadily rising since November, when Covid vaccines were found to be effective. On Friday, the value of the UK's mid-cap companies hit an all-time high. But their winning streak could have further to run, offering investors ample opportunity to benefit. Fast mover: The next James Bond film No Time To Die could boost the FTSE 250 high performer Cineworld What are mid-cap companies?